GM Service Manual Online
For 1990-2009 cars only

Displays Test

Certain instrument panel cluster (IPC) features are tested when the ignition is turned ON in order to verify the features are working properly. The following indicators illuminate briefly at key up unless otherwise noted:

    • Antilock Brake System (ABS) Indicator
    • Battery Indicator
    • Brake System Indicator
    • Coolant Temperature Indicator
    • Engine Oil Pressure Indicator
    • Tire Pressure Low Indicator

Indicators and Warning Messages

Refer to Indicator/Warning Message Description and Operation .

Fuel Gage

The instrument panel cluster (IPC) displays the fuel level as determined by the engine control module (ECM). The IPC receives a GMLAN message from the body control module (BCM) indicating the fuel level volume. The fuel gage defaults to empty (E) if:

    • The ECM detects a malfunction in the fuel level sensor circuit.
    • The IPC detects a loss of GMLAN communications with the BCM.

When the fuel level is less than a certain low percentage, LOW FUEL message displays in the driver information center (DIC).

Odometer

The vehicle odometer is calculated and stored electronically in the body control module (BCM) and is sent via GMLAN to the instrument panel cluster (IPC) for display. The BCM calculates and stores the mileage based on the vehicle speed GMLAN message from the engine control module (ECM). The IPC displays the season odometer information from the BCM in the driver information center (DIC). If the stored VIN in the IPC matches the GMLAN VIN, the odometer data from the BCM will then be displayed. If the VINs do not match, the IPC will freeze the odometer value for the entire ignition cycle.

Speedometer

The instrument panel cluster (IPC) displays the vehicle speed based on GMLAN serial data message from the body control module (BCM). The BCM receives vehicle speed data from the engine control module (ECM) via the GMLAN serial data circuit. The speedometer will default to 0 km/h (0 mph) if:

    • The ECM detects a malfunction in the vehicle speed sensor circuit.
    • The BCM detects a loss of GMLAN communications with the ECM.
    • The IPC detects a loss of GMLAN communications with the BCM.

Tachometer

The instrument panel cluster (IPC) displays the engine speed as determined by the engine control module (ECM). The IPC receives a GMLAN message from the body control module (BCM) indicating the engine speed. The tachometer will default to 0 RPM if:

    • The ECM detects a malfunction in the engine speed sensor circuit.
    • The BCM detects a loss of GMLAN communications with the ECM.
    • The IPC detects a loss of GMLAN communications with the BCM.